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Altera_Forum's avatar
Altera_Forum
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16 years ago

CRC Compiler Settings

Hey, I am trying to use the CRC compiler to verify the CRC for the MAC level of ethernet. I am unable to simulate a version that matches an actual message. The Altera documentation does not provide any hint of the right configuration. I am using it with a 32-bit word input.

Thanks

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    I figured out the proper settings, see below. This is for byte wide input.

    Number of channels: one

    Datapath: 8 bits

    Symbols per word: one

    Process low-numbered bit in each symbol first: check

    Processing low-numbered symbols first: not checked

    Select: CRC-32

    Starting value: 1's

    Number of leading bits ignored in the first word: 0

    Negate checksum: Check

    Bit-swap checksum: Check
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    Hi,

    I am trying to integrate CRC-CCITT into my Cyclone III design. It synthesizes etc fine but if I add the input and outputs of the core to my SignalTap design, I start getting instance mismatch error, i.e., 'Not compatible with the device'. Could someone please shed light on why this may be happening. Just to clarify, the FPGA is in un-tethered mode (its on a board with no internet access).

    Thanks